PEDIATRICS Vol. 90 No. 2 August 1992, pp. 207-211
This Article
Right arrow Full Text (PDF)
Right arrow P3Rs: Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when P3Rs are posted
Right arrow Alert me if a correction is posted
Services
Right arrow E-mail this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My File Cabinet
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via CrossRef
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Alemzadeh, R.
Right arrow Articles by Lifshitz, F.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Alemzadeh, R.
Right arrow Articles by Lifshitz, F.

Is There Compensated Hypothyroidism in Infancy?

Ramin Alemzadeh MD1, Silvia Friedman PhD1, Pavel Fort MD1, Bridget Recker RN, EdM1, and Fima Lifshitz MD1

1 From the Department of Pediatrics, North Shore University Hospital-Cornell University Medical College, Manhasset, NY; and Department of Pediatrics, Maimonides Medical Center, Brooklyn, NY

The state-mandated newborn thyroid screening program may uncover infants who exhibit normal thyoxine (T4) levels with various degrees of hyperthyrotropinemia. To elucidate further the thyroid status, the basal metabolic rate (BMR) of 10 infants (7 boys, 3 girls; aged 9 to 63 days) was studied by indirect calorimetry. They were clinically euthyroid and healthy with no evidence of overt biochemical hypothyroidism (low T4, high thyroid-stimulating hormone [TSH]). Confirmatory testing indicated that all infants had normal serum T4 levels for age (mean ± SD: 10.3 ± 3.2 µg/dL). However, serum TSH levels varied from 2.3 to 99.2 µU/mL In 4 infants (2 boys, 2 girls) the BMR was low (38.1 ± 4.1 kcal/kg per day), while the other 6 patients (5 boys, 1 girl) demonstrated BMRs within the normal range (49.6 ± 1.9 kcal/kg per day, P < .001). The serum TSH levels were above 7.0 µU/mL among those infants with a low BMR, whereas the serum TSH levels were always below 6.0 µU/mL among the normometabolic infants. All infants who had a low BMR received thyroid therapy and promptly became normometabolic (BMR: 48.7 ± 1.0 kcal/kg per day) with suppression of TSH levels (3.2 ± 1.3 µU/mL) within 3 weeks of therapy, while their serum T4 levels remained within the normal range. The observed normalization of BMR In parallel to reduction of TSH levels following thyroid replacement therapy strongly suggests that these patients demonstrated a hypometabolic state, despite normal serum T4 levels. Therefore, the assessment of BMR may help define subclinical hypothyroidism in infancy in conjunction with a close monitoring of TSH concentration.

Key Words: congenital hypothyroidism • infantile hyperthyrotropinemia • basal metabolic rate

Submitted on July 16, 1991
Accepted on January 3, 1992




This article has been cited by other articles:


Home page
 AAP Grand RoundsHome page
S. K. Varma
"False-Positive" Newborn Thyroid Screen May Predict Future Subclinical Hypothyroidism
AAP Grand Rounds, September 1, 2008; 20(3): 31 - 32.
[Full Text] [PDF]

Home page
 J. Clin. Endocrinol. Metab.Home page
F. Calaciura, R. M. Motta, G. Miscio, G. Fichera, D. Leonardi, A. Carta, V. Trischitta, V. Tassi, L. Sava, and R. Vigneri
Subclinical Hypothyroidism in Early Childhood: A Frequent Outcome of Transient Neonatal Hyperthyrotropinemia
J. Clin. Endocrinol. Metab., July 1, 2002; 87(7): 3209 - 3214.
[Abstract] [Full Text] [PDF]

Home page
 J. Clin. Endocrinol. Metab.Home page
Diagnosis of Hidden Central Hypothyroidism in Survivors of Childhood Cancer
J. Clin. Endocrinol. Metab., December 1, 1999; 84(12): 4472 - 4479.
[Abstract] [Full Text]

Home page
 J. Am. Coll. Nutr.Home page
C. R. Cole, R. Rising, A. Hakim, M. Danon, R. Mehta, S. Choudhury, M. Sundaresh, and F. Lifshitz
Comprehensive Assessment of the Components of Energy Expenditure in Infants Using a New Infant Respiratory Chamber
J. Am. Coll. Nutr., June 1, 1999; 18(3): 233 - 241.
[Abstract] [Full Text] [PDF]